Radio signal processing apparatus of portable telephone for sharing digital/analog compatible mode and personal communication service mode

Abstract

A radio signal processing apparatus of a portable telephone which can share a first transmit/receive mode such as a digital/analog (D/A) compatible mode and second transmit/receive mode such as a personal communication service (PCS) mode. The radio signal processing apparatus includes: a frequency generator for generating frequencies necessary for a frequency conversion; a first mode converter for converting a frequency of a signal transmitted and received in the first mode according to a prescribed oscillating frequency generated from the frequency generator; a second mode converter for converting a frequency of a signal transmitted and received in the second mode according to a prescribed oscillating frequency generated from the frequency generator; an intermediate frequency processor for converting, transmitting and receiving intermediate frequencies according to a prescribed oscillating frequency generated from the frequency generator; a first switch for selectively connecting an antenna to the first mode converter or the second mode converter; and a second switch for selectively connecting the first mode converter or the second mode converter to the intermediate frequency processor.

What is claimed is: 
     
       1. A radio signal processing apparatus of a portable telephone which can share a first transmit/receive mode and a second transmit/receive mode, comprising: a frequency generator for generating frequencies necessary for a frequency conversion;   a first mode converter for converting a frequency of a signal transmitted and received in said first mode according to a prescribed oscillating frequency generated from said frequency generator;   a second mode converter for converting a frequency of a signal transmitted and received in said second mode according to a prescribed oscillating frequency generated from said frequency generator;   an intermediate frequency processor for converting, transmitting and receiving intermediate frequencies according to a prescribed oscillating frequency generated from said frequency generator;   a first switch for selectively connecting an antenna to one of said first mode converter and said second mode converter according to a mode selection of a user; and   a second switch for selectively connecting one of said first mode converter and said second mode converter to said intermediate frequency processor according to a mode selection of a user.   
     
     
       2. The apparatus of claim 1, wherein the first mode is a digital/analog compatible mode and the second mode is a personal communication service mode. 
     
     
       3. The apparatus of claim 2, wherein said digital/analog compatible converter comprises: a first duplexer for transmitting or receiving a signal to and from said first switch;   a digital/analog compatible receiving signal converter for converting a signal received through said first duplexer into an intermediate frequency signal according to a prescribed oscillating frequency generated from said frequency generator; and   a digital/analog compatible transmitting signal converter for converting an intermediate frequency signal received through said second switch into a transmitting signal according to a prescribed oscillating frequency generated from said frequency generator.   
     
     
       4. The apparatus of claim 3, wherein said personal communication service converter comprises: a second duplexer for transmitting or receiving a signal to and from said first switch;   a personal communication service receiving signal converter for converting a signal received through said second duplexer into an intermediate frequency signal according to a prescribed oscillating frequency generated from said frequency generator; and   a personal communication service transmitting signal converter for converting an intermediate frequency signal received through said second switch into a transmitting signal according to a prescribed oscillating frequency generated from said frequency generator.   
     
     
       5. The apparatus of claim 4, wherein said second switch comprises: a switch for selectively connecting one of said digital/analog compatible receiving signal converter and said personal communication service receiving signal converter to said intermediate frequency processor according to a mode selection of a user; and   another switch for selectively connecting one of said digital/analog compatible transmitting signal converter and said personal communication service transmitting signal converter to said intermediate frequency processor according to a mode selection of a user.   
     
     
       6. The apparatus of claim 4, wherein said personal communication service receiving signal converter comprises: a second low-noise amplifier for low-noise amplifying a receiving signal;   a fourth band pass filter for filtering the low-noise amplified signal to a prescribed pass frequency band;   a third multiplier for doubling a prescribed oscillating frequency generated from said frequency generator and generating a local oscillating signal; and   a fourth mixer for mixing a signal filtered through said fourth band pass filter with said local oscillating signal generated from said third multiplier and generating an intermediate frequency signal.   
     
     
       7. The apparatus of claim 6, wherein said personal communication service transmitting signal converter comprises: a fourth multiplier for doubling a prescribed oscillating frequency generated from said frequency generator and generating a local oscillating signal; and   a fifth mixer for mixing an intermediate frequency signal supplied through said second switch from said intermediate frequency processor with said local oscillating signal generated from said fourth multiplier and generating a transmitting signal;   a fifth band pass filter for filtering said transmitting signal generated from said fifth mixer to a prescribed pass frequency band; and   a second power amplifier for power-amplifying a signal generated from said fifth band pass filter and generating the power-amplified signal through said second duplexer.   
     
     
       8. The apparatus of claim 2, wherein said digital/analog compatible receiving signal converter comprises: a first low-noise amplifier for low-noise amplifying a receiving signal;   a first band pass filter for filtering the low-noise amplified signal to a prescribed pass frequency band;   a first multiplier for multiplying a prescribed oscillating frequency generated from said frequency generator by one and generating a local oscillating signal; and   a first mixer for mixing the filtered signal with said local oscillating signal and generating an intermediate frequency signal.   
     
     
       9. The apparatus of claim 8, wherein said digital/analog compatible transmitting signal converter comprises: a second multiplier for multiplying an oscillating frequency generated from said frequency generator by one and generating a local oscillating signal;   an oscillating for oscillating a prescribed frequency;   a second mixer for mixing an intermediate frequency signal supplied through said second switch from said intermediate frequency processor with an oscillating signal generated from said oscillator;   a second band pass filter for filtering a signal generated from said second mixer to a prescribed pass frequency band;   a third mixer for mixing said local oscillating signal generated from said second multiplier with a signal generated from said second band pass filter and generating a transmitting signal;   a third band pass filter for filtering said transmitting signal generated from said third mixer to a prescribed pass frequency band; and   a first power amplifier for power-amplifying a signal generated from said third band pass filter and generating the power-amplified signal through said first duplexer.